Journal article

Observation of the rare B-s(0)->mu( )mu(-) decay from the combined analysis of CMS and LHCb data

V Khachatryan, AM Sirunyan, A Tumasyan, W Adam, T Bergauer, M Dragicevic, J Eroe, M Friedl, R Fruehwirth, VM Ghete, C Hartl, N Hoermann, J Hrubec, M Jeitler, W Kiesenhofer, V Knuenz, M Krammer, I Kraetschmer, D Liko, I Mikulec Show all



The standard model of particle physics describes the fundamental particles and their interactions via the strong, electromagnetic and weak forces. It provides precise predictions for measurable quantities that can be tested experimentally. The probabilities, or branching fractions, of the strange B meson (B(s)(0)) and the B0 meson decaying into two oppositely charged muons (μ+ and μ−) are especially interesting because of their sensitivity to theories that extend the standard model. The standard model predicts that the B(s)(0) →µ+µ− and B(0) →µ+µ− decays are very rare, with about four of the former occurring for every billion mesons produced, and one of the latter occurring for every ten bil..

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Funding Acknowledgements

We express our gratitude to colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at CERN, at the CMS institutes and at the LHCb institutes. In addition, we gratefully acknowledge the computing centres and personnel of the Worldwide LHC Computing Grid for delivering so effectively the computing infrastructure essential to our analyses. Finally, we acknowledge the enduring support for the construction and operation of the LHC, the CMS and the LHCb detectors provided by CERN and by many funding agencies. The following agencies provide support for both CMS and LHCb: CAPES, CNPq, FAPERJ and FINEP (Brazil); NSFC (China); CNRS/IN2P3 (France); BMBF, DFG and HGF (Germany); SFI (Ireland); INFN (Italy); NASU (Ukraine); STFC (UK); and NSF (USA). Agencies that provide support for CMS only are BMWFW and FWF (Austria); FNRS and FWO (Belgium); FAPESP (Brazil); MES (Bulgaria); CAS and MoST (China); COLCIENCIAS (Colombia); MSES and CSF (Croatia); RPF (Cyprus); MoER, ERC IUT and ERDF (Estonia); Academy of Finland, MEC, and HIP (Finland); CEA (France); GSRT (Greece); OTKA and NIH (Hungary); DAE and DST (India); IPM (Iran); NRF and WCU (Republic of Korea); LAS (Lithuania); MOE and UM (Malaysia); CINVESTAV, CONACYT, SEP, and UASLP-FAI (Mexico); MBIE (New Zealand); PAEC (Pakistan); MSHE and NSC (Poland); FCT (Portugal); JINR (Dubna); MON, RosAtom, RAS and RFBR (Russia); MESTD (Serbia); SEIDI and CPAN (Spain); Swiss Funding Agencies (Switzerland); MST (Taipei); ThEPCenter, IPST, STAR and NSTDA (Thailand); TUBITAK and TAEK (Turkey); SFFR (Ukraine); and DOE (USA). Agencies that provide support for only LHCb are: FINEP (Brazil); MPG (Germany); FOM and NWO (The Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MinES and FANO (Russia); MinECo (Spain); SNSF and SER (Switzerland). Individuals from the CMS collaboration have received support from the Marie-Curie programme and the European Research Council and EPLANET (European Union); the Leventis Foundation; the A. P. Sloan Foundation; the Alexander von Humboldt Foundation; the Belgian Federal Science Policy Office; the Fonds pour la Formation a la Recherche dans l'Industrie et dans l'Agriculture (FRIABelgium); the Agentschap voor Innovatie door Wetenschap en Technologie (IWT-Belgium); the Ministry of Education, Youth and Sports (MEYS) of the Czech Republic; the Council of Science and Industrial Research, India; the HOMING PLUS programme of Foundation for Polish Science, cofinanced from European Union, Regional Development Fund; the Compagnia di San Paolo (Torino); the Consorzio per la Fisica (Trieste); MIUR project 20108T4XTM (Italy); the Thalis and Aristeia programmes cofinanced by EU-ESF and the Greek NSRF; and the National Priorities Research Program by Qatar National Research Fund. Individual groups or members of the LHCb collaboration have received support from EPLANET, Marie Sklodowska-Curie Actions and ERC (European Union), Conseil general de Haute-Savoie, Labex ENIGMASS and OCEVU, Region Auvergne (France), RFBR (Russia), XuntaGal and GENCAT (Spain), Royal Society and Royal Commission for the Exhibition of 1851 (UK). LHCb is also thankful for the computing resources and the access to software R&D tools provided by Yandex LLC (Russia). The CMS and LHCb collaborations are indebted to the communities behind the multiple open source software packages on which they depend.